#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;

class Solution {
public:
	vector<vector<int>> generate(int numRows) {
		vector<vector<int>> ans;
		for (int i = 0; i < numRows; i++) {
			vector<int> temp;
			for (int j = 0; j <= i; j++) {
				if (j == 0 || j == i)
					temp.push_back(1);
				else
					temp.push_back(ans[i - 1][j - 1] + ans[i - 1][j]);
			}
			ans.push_back(temp);
		}
		return ans;
	}
};

void main() {
	Solution s;
	s.generate(30);
}